Attention deficit hyperactivity disorder (ADHD) is a developmental disorder characterized by symptoms such as impulsiveness, hyperactivity and/or inattentiveness. Hyperactivity is common among children with ADHD but tends to disappear during adulthood. However, over half of children with ADHD continue to have some symptoms of inattention throughout their lives.
Stimulant medications are widely used as a pharmacological treatment for ADHD. Stimulants, in the short term, have been found to be safe in the appropriately selected patient and appear well tolerated over five years of treatment. Active pharmaceutical agents now approved in the USA for use in treatment of ADHD are primarily effectors of the dopamine or norepinephrine neural pathways. Approved agents include salts and isomers of amphetamine and methylphenidate, the dextroamphetamine prodrug, lisdexamfetamine dimesylate, and atomoxetine.
One of the challenges of treating ADHD and other CNS stimulant responsive conditions is delivering and maintaining an effective concentration in patients throughout the day and, in particular, in the morning hours when cognitive abilities and concentration are needed for school or work and in the late afternoon or evening when students often do homework. Early formulations relied on a twice daily administration of an immediate release formulation, causing problems with compliance. Various long-acting formulations were developed and are now available that have been shown in clinical trials to be effective for 8-14 hours (Brains et al., Current Medical Research and Opinion, vol. 26 no. 8, pgs 1809-1825, August 2010).